This invention relates to communications in the distribution system for a utility such as water, gas, or electrical utilities which may have numerous urban, suburban, and rural customers. More particularly, the invention relates to a multi-tiered communication system by which the utility can, among other things, quickly and reliably communicate with its customers, regardless of their location, so to ascertain information concerning the utility's operation throughout the system. This would include, for example, determining if there is an electrical outage within the system, or a gas line or water line break, the extent of any resulting problem, controlling and managing the utility's field workforce, monitoring the utility's assets where they are located (i.e., in situ), control of the distribution components of the utility in a timely manner, implement security monitoring when needed, and control of the level of demand during peak periods of usage of the electricity, gas, or water provided by the utility.
Electrical, water, and gas utilities serve a wide variety of customers. It is commonplace for a utility to provide a commodity such as water, gas, or electricity to consumers in urban, densely populated areas, suburban areas which are not so densely populated and rural areas where there are often substantial distances between customers. It is also commonplace for the utility to provide service to industrial consumers who place very rigorous demands on the utility; to businesses of many types which, while perhaps not as demanding, still may have unique requirements; and, to residential customers whose demands are relatively uniform across a broad spectrum of customers.
Heretofore, it has been difficult for a utility to provide a service unique to each individual customer. There are a number of reasons for this. First, it will be recognized that a utility operates at a number of different levels. Topmost is the overall system. At this level, the utility needs to be cognizant of the gross demand on its generating and/or delivery capability and its distribution system, and determining if it is operating near or at capacity. For an electrical utility, for example, this can include determining if it needs to timely bring additional generating capacity on-line, buy additional electricity in the marketplace to accommodate short term peak demands and prevent blackouts or brownouts, or institute a load shedding or demand response protocol by which load on the system is reduced to levels of consumption which the utility can sustain with its available generating capacity. Likewise, water and gas utilities have unique needs that must be met. For example, during times of drought, a water utility may need to monitor and control water consumption and prevent unnecessary or extravagant usages of water. Gas utilities, for example, may need to monitor gas consumption, gas line pressures throughout the system, cathodic corrosion, etc. This monitoring is accomplished using a number of sensor based communication points strategically located throughout the utility's distribution area.
The next level relates to various regions in the system. While these regions are primarily geographic (urban, suburban, rural), each region usually includes a number of sub-regions. At this level, an electrical utility, for example, is concerned about distribution matters such as power outages which tend to be localized; although it will be appreciated that a number of outages can occur at the same time (as, for example, during a storm). Further, utilities supplying electricity, water, or gas, experience periods of peak demands within different regions. For example, in urban areas where manufacturing industries and large businesses tend to be clustered, higher or peak demands are typically experienced during the daytime hours (mid-morning to late afternoon) while suburban (residential) areas tend to experience higher or peak demands during early-morning, late-afternoon, and evening hours when people are at home.
Third, is the level of individual users or consumption points. This level involves such things as automatically reading multiple utility meters installed at a customer's location to determine current and overall commodity consumption. For communication purposes, a meter is installed at each customer's location. An electrical utility then has the ability to communicate with all of the meters on the same feeder line to determine, for example, if there is an electrical outage in a particular region and, if so, its extent. The utility can also communicate through the meter to control the amount of electrical usage in a region at times of peak demand. It does this using load control equipment in communication with the meter. Further, the meter can communicate with the utility at anytime (i.e., an unsolicited communication) if an outage occurs at the location of the meter, or for other reasons.
Because of the range of population density within the geographic area serviced by a utility, some utilities have found it advantageous to communicate with their customers using various different methods. In highly populated urban and suburban areas, utilities have started using a radio-frequency (RF) based communications system in which data and other information is transmitted to and from electrical, gas and water meters, load control units, and other devices via RF. In outlying, lesser populated areas, communications to and from users' devices are sent over transmissions lines using, for example, a two-way automated communications system such as TWACS® which is used by electrical utilities.
With respect to RF communications, utilities are now investigation the use of a wireless mesh network (WMN). Such a network typically comprises a number of radio nodes organized according to some topology. An advantage of a properly deployed WMN is that it provides a high bandwidth communications path which can carry substantial amounts of data and other information over the area of coverage when operating in a multi-tier configuration.